This provision details the mandatory Value Added Tax registration requirements for non-resident persons in the Kingdom of Saudi Arabia. Under Article 5 of the Implementing Regulations, any non-resident who is not registered but becomes obligated to pay VAT on supplies made or received in the Kingdom must apply for registration with the Authority. The application must be submitted within thirty days of the first supply on which the obligation to pay tax arose. The effective date of the registration is the date of that first supply, ensuring comprehensive tax compliance from the initial transaction.